The purpose of this study is to assess a hypothesized association between certain oral conditions and risk of developing acquired immunodeficiency syndrome (AIDS) and the AIDS-related complex (ARC) in individuals exposed to the human immunodeficiency (HIV) virus. The prevalence of oral malignancies such as Kaposi's sarcoma and certain non-malignant oral conditions, such as Candida albicans, Condyloma acuminatum, hairy leukoplakia and acute necrotizing ulcerative gingivitis will be determined in seropositive patients relative to seronegative individuals. The major goals of this study are (i) to confirm and extend the findings of previous studies, and (ii) to generate pilot data for a prospective study intended to address the antecedent-consequent relationship of these previously reported associations. If certain oral manifestations are found to precede development of active disease in seropositive individuals, this information could be useful as a screen for high risk individuals and as prognostic indicators for early patient referral. This may prove important if early drug intervention is shown to improve the prognosis by extending the life of the patient. Therefore the primary significance of this study is in its potential to elucidate oral conditions which may provide suggestive evidence of a patient's decreasing immunocompetence. Data will be obtained on individuals seeking information and counseling at the Seattle-King County Department of Public Health AIDS Prevention Project, using a patient-administered questionnaire and a clinical evaluation of the patient's oral condition. Histologic verification and photographic documentation of oral lesions will be sought. Seropositive and seronegative individuals will be included, using a selection ratio of one. The data will be analyzed using standard epidemiologic methods for cross-sectional studies.